Demco Butterfly Valve Demco Butterfly Valves available from; Size: 2 " - 24" . Type: Wafer, Lug. Type: NE-C, NE-I, NE-D, NF-C. Ready Stock Type NE-C, Wafer, 2, 3 " , 4" , 5 " , 6" , 8 " , 10" , 12 " ANSI 150 Wafer, Gray Iron Body, 416 SS Stem, Nickle Plated Ductile Iron Disc, Buna-N seat, 10 position locking handle.